Number two priority for hearing impaired people is to improve the listening situation when talking into a phone (number one priority being to improve direct voice or sound inputs in noisy listening situations).
Various intermediate devices, which handle the communication between a mobile telephone and a hearing aid, by providing a Bluetooth link to the mobile phone, have been defined. Examples of such devices are e.g. described in EP 1 460 769 A1 and WO 2006/117365 A1. However, landline and cordless telephones do typically not have Bluetooth capabilities. Furthermore, intermediate devices are not wanted by the end user as they have to be carried at all times (in addition to the hearing instruments and the phone) and can be complicated to set up and use (involving Bluetooth pairing, setup, call answering, switching mode, etc.).
Most hearing instruments support the use of a telecoil picking up the sound from the receiver of a phone. This solution does, however, not provide good sound quality and is prone to interference.
EP 0 872 032 B1 describes a short range communication system using inductive communication between a base unit and a portable unit allowing for two way communication between them. The base unit can e.g. be a mobile telephone or a handset of a cordless telephone system. The portable unit can e.g. be a headset.
EP 1 903 755 A2 describes a mobile wireless device which uses a magnetic coil equipped in a vibration motor for generating a hearing aid-compatible magnetic signal without requiring an additional T-coil.